<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>Title</title>
  <script src="https://unpkg.com/vue@next"></script>
</head>
<body>
<div id="root"></div>
</body>
<script>
  const app = Vue.createApp({
    template: `
    <hello></hello>
    <world></world>
    `,
  })
  app.component('counter', {
    template: `
    <div>hello</div>
    `
  })
  app.mount('#root');
</script>
</html>